Snowplow



Oct. 10, 1933. G. c. souLE Er AL SNOWPLOW Filed Sept. 29, 1930 4 SheetS-Sheet l w? WMM Ja w w Oct. 10, 1933. G. c. ouLE ET A1.

SNOWPLOW Filed Sept. 29, 1930 4 Sheets-Sheet 2 INVENToRs.

John B.Waod2ur y. Geolzqe CJoule.

JVTTO NE Y.

Oct. 10, 1933. G C SOULE ET AL 1,929,958

sNwPLow Filed Sep't. 29, 1930 4 Shee'S-Sheet 3 J'? TToR N l4v Sheets-Sheet 4 IN vE/vrofzs.

John B. VVoodbur George C-'oule.

I JTTO ;y-K

G.'C. SOULE Er AL SNOWPLOW Filed-Sept. 29, 1930 Oct. 10, 1933.

Patented Oct. 10, 1933 UNITED' STATES SNOWPLOW George o. some and John B. woodbury, Smithv Portland, Maine, assignors to Maine Steel Products Company, Portland, Maine, a corporation of Maine Application September 29, 1930 Serial No. 485,256

3 Claims.

Our present invention relates to snow plow equipment and involves various improvements in such structures, particularly in apparatus of the hydraulically controlled type.

Such a type of apparatus usually is intended to be used with a tractor as a propulsive vehicle. The adjustment of nose and wings in such heavy equipment have involved various difiiculties.

Where the weight of the nose is carried on the tractor frame, difiiculty has been experienced in getting proper support and one of the features of the present invention involves a novel type of such support. The adjustments of wing and nose have to be made rapidly and usually with frequent changes and in all conditions of weather and low temperature. An important feature in the present invention involves the con- Vcept of a hydraulic operation of the parts through Operating cylinders which are controlled by an intermittently operated pump in the cab, which may be of comparatively inexpensive manually operated'type. This is a feature of very great importance as it permits of inexpensive equipment or equipment less expensive than that which is power operated and yet permits the operator, whether driver or vattendant, to be within the cab and not exposed to low temperature or stormy weather. These and various other features are shown in an illustrative embodiv ment as set forth in the accompanying drawings.

In these drawings:

Fig.` 1 is a side elevation of the snow plow.

Fig. 2 is afragmentary rear elevationof the same.

Fig. 3 is a plan view of the nose-lifting unit, showing double sheave arrangement.

Figs. 4 and 5 represent side elevations of the respective pairs of sheaves in the main hoisting block.

Fig. 6 is a perspective of the power unit, including the pumps, reservoir for oil and the lifting cylinders.

Fig. 7 is a fragmentary perspective view of one rear corner of the snow plow.

Fig. 8 is a' section through a characteristic fiuid pressure equipment.

Fig. 9 is a section through the valve chest.

Figs. 10, 11, and 12 are fragmentary Sections on the line 10-10, Fig. 8, showing three different Operating positions of one of the valves.

In the illustrative embodiment shown, the snow plow equipment comprises a frame consisting of longitudinal bottom members 1 having a runner 2 the longitudinal members 1 being connected across at their'rear end by a removable draw bar 3 which may be opened up to permit the entry of the tractor indicated generallyat T.

The draw bar is shackled to the rear of the tractor by any suitable connection as at 4. In the form shown this connection is made to a reartractor platform 5. At the forward end,

the main side frames 1 carry a nose 6 which may be of any desired construction. Running longitudinally of the plow frame at each side are levers 7 fulcrumed at 8 on a support 9 carried on the frame of the tractor T and preferably located centrally of its 'tractive base. The forward end of each lever is connected as at 10 'to brackets 11 on the plow nose. The ends of the levers 7 are cross connected as at 12 and the nose 6 is raised and lowered by a hydraulic system which is connected with this lever 12.

In addition to the nose control, the equipment shown is provided with a lateral wing 13, pivoted on the slide 14 mounted on the forward column 15. The wing 13 is backed up by a strut arm 16 pvotally connected at one end to the wing as at 17 and at its inner end to a slide 18 mounted on a column 19.

Mounted on the rear platform 5 of the tractor is a platform 20 which carries the cylinder unit 21 for Operating the nose. The two lateral cylinders 22 control their respective wings. These cylinders operate suitable fiexible cables with the respective hoists which they operate as will be apparent from the drawings.

The cylinders 21 and 22 are shown in Fig. 6 connected by their pipe lines 23 and 24 with a reserve tank 25. This tank contains the fluid medium, such medium being forced by an intermittently operable pump 26, shown in the drawings as operable by a handle 31, through the lines 23 and 24. The lines 23 and 24 lead to a control valve housing 27 which is in direct connection with the tank or receiver 25.

The valve housing 27 contains three separate valves each controlled by a valve lever 28, 29, 30. The valves controlled by these levers each control one of the lines 23, 24, that indicated at 28 controlling the central cylinder 21 which is the cylinder Operating the nose hoist. The lever 29 controls the right hand hoisting cylinder and the lever 30 the left hand hoisting cylinder.

In Operating the apparatus, and, for instance, in case the nose is to be raised or lifted, the valve lever 28 is swung into a position in which line 23 is connected therewith. The pump lever 31 is then operated as desired by the driver or assistant and pressure applied to cylinder 21 to raise the nose. Each valve and line is operated by the pump independently`,.each being independently connected to the pump. It is, therefore, possible to operate either wing while the nose cylinder is operated, or to operate the nose cylinder whileeither or both wings 'are operated. and to operateto just the degree desired.

One of the characteristic features of the present invention concerns the unique method of remote control of the hydraulically operated hoist for elevating the wings and nose of the snow plow.

The pump being manually actuated by the operator of the snow plow enables him more accurately to gau'ge the elevating of the snow plow elements as the whole mechanism is under his immediate observation.

While the apparatus, due to the manner in which it is operated, must necessarily be constructed on somewhat differentlines than is the mechanism employed on heavier duty, powerdriven hoists, there are, under our present in- 'vention advantages over the latter, apart fro`m the matter just recited, one being the initial low cost of manufacture.

In the manual control, the objects sought are attained by the use of a considerably simplified construction, and if reference be had to Figs. 8

to 12 inclusive an understanding of both the structural and Operating features of the invention may be had.

Within the valve chest 27 are three independently operated valves, in the present instance of the oscillating type. These three valves are, as previously stated, actuated by the respective handles 28, 29 and 30.

In Fig. 9 is shown a horizontal section through the valve chest and through the valve housings 32, 33 and 34, in each of which operates the oscillatory valve similar to that shown in Fig. 8, which is a Vertical section through the apparatus.

In each valve housing are three ports a, b and c, the first being directly connected With the pressure chamber 35, the second with the space 36 in the valve chest, and the last communicating with one. of the hoisting cylinders 21, 22 or 22 through one of the connecting pipes 23, 24 or 25, respectively.

The valve assembly comprises the valve proper 37, operable in the valve holder 38 and subject to a strong but yieldng pressure against the wall of the valve vhousing through the agency of the spring 39.

In the valve is an open-ended passageway 40, the object of which may be understood by reference to Figs. 10, 11, and 12, which illustrateV three different positions of one of the valves. The views disclose the sequence of Operations thereof to admit the pressure conveying fiuid to the hoisting cylinder, to hold the piston in the cylinder fixed at any desired elevation, and to release the fiuid from lthe cylinder and permit it to return to the reserve supply of oil in the' reservoir 25, the oil in which is never under pressure.

In Fig. 10, we have indicated by arrows the fiow of the oil, or pressure conveying fiuid, passing from the pressure chamber 35 through the port a, thence through the ported passageway 40 into the port c out of which the oil proceeds to the lifting cylinder and accomplishes the raising of the piston therein to effect the proper elevation of the snow plow part being operated on.

We preferably employ two single-acting pumps making common connection with the passage- Way 26' in which there is an admission check .valve 41 and a discharge check valve 42, the fiuid under pressure from the pumps passing upwardly through the pipe 43 to the chamber 35.

When the operator ,has raised the particular 'snow'plow part, Wing or nose, to the desired elecylinder is heid at a fixed eievatio'n.

Later, when it becomesnecessary to lower the part raised, the operator simply rotates the valve into the position indicated in Fig. 12. In this location of the valve the port a is still blocked but the ports b and c are open, thus permitting the oil to escape or return as indicated by arrow through the pipe in which it was conveyed to the cylinder, and, after entering the chamber 36 drop to the-oil reservoir 25.

It will be understood 'that the valve may be oscillated from position shown inFig. 11 to that in Fig. 12, and vice versa, to permit so much only of the oil to escape or be released to the reservoir as will lower the piston the desired amount. If left as in Fig. 12 the oil will fully escape from beneath the piston and the plow part will fall to the ground.

The handles 28, 29 and 30 may be frictionally held to locate the valve in any one of its three vpositions by the engagement of the tailpiece 29' with notches in a projection 44 on the top of the valve chest.

While this pressure system and its controls as shown have certain advantages, other or modified forms may be used. The arrangement of the cylinders or hoisting unit may be variously located or constructed. Our invention contemplates plows of various styles or types and variously rigged or propelled as the equipment shown while representing a very complete development is, of course, only one of many types and to be understood as illustrative.

v What we therefore claim and desire to secure by Letters Patent is:

1. In a fiuid control of the type which employs a plurality of pressure operated jacks, a fiuid supply tank, individual feed pipes from said tank 110 to the cylinders of said jacks and a pump mounted on said tank for drawing fluid from said tank and selectively sending it through said feed pipe, the combination therewith of a valve chest surmounting said tank'and having a release chamber communicating with said tank and a pressure chamber communicating with said pump, a plurality of valve housings, one for each jack, mounted within said valve chest and radially disposed with reference to said pressure chamber, each 120 valve housing having a pressure port communicating directly with said pressure chamber, a release port communicating with said release chamber and a feed. port communicating with one of said feed pipes, a three-way valve manipulatable within each valve housing, each valve having a passageway therein effective in one position of the valve to connect the pressure port of its valve housing with the feed port thereof while blocking the release port, in another position to destroy such communication of the pressure and feed ports while still blocking said release port and in a third position to block the pressureport while placing the release port in communication with the feed port, and an individual Operating mechanism for each valve and mounted on said valve chest.

2. A control as claimed in claim 1, wherein the communication of the pressure chamber with the pump is by means of'a pipe extending axially 140 of the supply tank.

3.A control as claimed in claim 1, wherein. the communication of the pressure chamber lwith the pump is by means of a' pipe extending axially ofvthe *supply tank and the supply tank has 145 'a return connection to the pump between the tank and said aiial pipe.

JOHN B. WOODBURY.

GEORGE C. SOULE. 

